Help pls....

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Castielzed

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Apr 18, 2016
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Hi guys, just a quick question on mods with more than 1 battery.

If im using a mod with 3 batteries does that mean, assuming they are all full charged: i have 12.6volts (4.2x3), 60amps(20x3) CDR?
So if im checking for the Actual discharge rate for my coil (.35ohms) the should it be like this? 12.6v/.35ohm=36a CDR????

Thanks in advance for helping



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bacc.vap

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If your batteries are wired in series you add the voltage together and you'd get the 12.6 volts. If they are wired in parallel the voltage stays at 4.2 volts. Yes it would be 36amps for the 12.6@.35 ohms, and 12amps for 4.2volts@.35ohms. This is a mechanical you're using , right?
 
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Castielzed

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Apr 18, 2016
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If your batteries are wired in series you add the voltage together and you'd get the 12.6 volts. If they are wired in parallel the voltage stays at 4.2 volts. Yes it would be 36amps for the 12.6@.35 ohms, and 12amps for 4.2volts@.35ohms. This is a mechanical you're using , right?

Actually it's an rx200 [emoji16] im just curious on how i can apply the safety calculations of a mech mod...

So if its series then i have a CDR or 60amps?
 
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speedy_r6

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If you have an rx200, dont worry about ohms. As long as they are within the device parameters, they are fine. Worry about your watts. Assume the device has a cutoff voltage of 3.2v per cell. That means 9.6v in series. Divide the watts you are running by 9.6v. That will tell you how many amps are being drawn from each battery. I like to leave 25% overhead for safety(only drawing 15 amps if they are rated for 20. Only drawing 22.5 if they are rated for 30.). If you keep a 25% margin of safety, you can go to 144 watts on 20 amp batteries or 216 watts(assuming you updated it to be able to do 250w) on 30 amp batteries.
 

suprtrkr

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Ohhh thanks a lot! So meaning if i have 3 batts in parallel then i can build coils that require even above 30amps cdr?
You can, but there's no real sense in it. You won't find a parallel regulated mod, or not many, (the calculations are different anyway) because voltage is easier to manipulate, so series is the way to go for that. A three-battery parallel box mech mod can, theoretically, take a coil down to .07Ω to make 60 amps on the load, but that is both insane and useless. A .07Ω resistance is the value battery testers use for dead short testing, for one thing. For another, once you get below about .2ish ohms, you start getting large efficiency losses (I²R losses) so great any actual improvement in watts is wasted and not applied to the coil, no matter how many batteries you have. On a mech, you're really limited to 85-90 watts in practice no matter how many batteries you maze up, and you can get that on a two-battery box.

The one thing you can do with multiple battery mechs that can increase your cloud without serious danger or wasting all the extra watts you're generating, is to build an atty that will take 6 or 8 coils. But bear in mind, if you have an octo-coil atty, and you stay at .2Ω, each individual coil has to be 1.6Ω. In practical terms, a regulated mod, with the capacity to increase voltage above battery volts, can more effectively use tall watts than a mech can. And, in general, a massive, huge surface area coil can make better cloud than a multitude of smaller, slick wire coils, at the expense of some ramp time to heat all that wire up. It's not about watts, or not entirely. It's mostly about power radiated from the coil surface in contact with wet wick, and there's more than one way to get there.
 

Susan~S

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Actually it's an rx200
emoji16.png
im just curious on how i can apply the safety calculations of a mech mod...
When using a regulated mod you do not apply ohms law, it's watts law that applies. The resistance of your coil has no bearing on safety when using a regulated mod. As long as the resistance falls within your devises parameters you are good.

As far as battery safety, here's the calculation that applies when using a regulated mod: Calculating Battery Current Draw for a Regulated Mod
 

Castielzed

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Apr 18, 2016
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When using a regulated mod you do not apply ohms law, it's watts law that applies. The resistance of your coil has no bearing on safety when using a regulated mod. As long as the resistance falls within your devises parameters you are good.

As far as battery safety, here's the calculation that applies when using a regulated mod: Calculating Battery Current Draw for a Regulated Mod

Thanks
I think the link is not what i think it is :)
 
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